The present invention relates generally to welding systems and, more particularly, to a welding stud for stud welding applications.
Stud welding is a welding process that utilizes a localized burst of current between a metallic fastener and a metallic workpiece. A stud welding system has a power source, a stud gun, a pair of cables that connect the stud gun to the power source, and a stud that is welded to a workpiece. In most instances, although not required, the fastener and the workpiece have the same material properties. The fasteners are held and welded in place through the use of an electro-mechanical device in the stud gun.
Stud welding has applications in many industries. These industries include boiler manufacturing, ship building, auto manufacturing, and construction to name but a few. Welding a stud to a workpiece is an easy and efficient means of securing a fastener device to the workpiece. Studs are also provided in a variety of shapes and materials such that welding studs to a workpiece can be used to differentiate between further systems to be attached to the workpiece depending on the type of stud welded thereto.
The quality of the weld which attaches the stud to the workpiece partially determines the amount of load the stud can support. A poor quality weld can result in failure of the weld between the stud and the workpiece. Weld failure associated with poor weld quality is difficult to predict and is often designed around by over welding the stud rather than improving the welding efficiency of the weld stud. A low efficiency in the stud welding process is partially due to low, effective contact resistance between the stud and a workpiece.
The efficiency of the weld between the stud and the workpiece is partially determined by the physical construction of the welding stud used and the condition of the interface between the welding stud and the workpiece. A poor interface between the welding stud and the workpiece detrimentally affects arc performance and can result in weld failure. The physical construction of the weld end of the welding stud also affects the quality of a weld between a welding stud and a workpiece. If the weld end of the welding stud is poorly constructed, an incomplete weld can be formed between the welding stud and the workpiece after the termination of the welding process.
Therefore, it would be desirable to design a welding stud for stud welding applications that maximizes arc characteristics between the welding stud and the workpiece, thereby maximizing weld quality and welding efficiency.